Adaptive reconfigurable voting for enhanced reliability in medium-grained fault tolerant architectures

The impact of SRAM-based FPGAs is constantly growing in aerospace industry despite the fact that their volatile configuration memory is highly susceptible to radiation effects. Therefore, strong fault-handling mechanisms have to be developed in order to protect the design and make it capable of fighting against both soft and permanent errors. In this paper, a fully reconfigurable medium-grained triple modular redundancy (TMR) architecture which forms part of a runtime adaptive on-board processor (OBP) is presented. Fault mitigation is extended to the voting mechanism by applying our reconfiguration methodology not only to domain replicas but also to the voter itself. The proposed approach takes advantage of adaptive configuration placement and modular property of the OBP, thus allowing on-line creation of different medium-grained TMRs and selection of their granularity level. Consequently, we are able to narrow down the fault-affected area thus making the error recovery process faster and less power consuming. The conventional hardware based voting is supported by the ICAP-based one in order to additionally strengthen the reconfigurable intermediate voting. In addition, the implementation methodology ensures using only one memory footprint for all voters and their voting adaptations thus saving storing resources in expensive rad-hard memories

Methods of surface ionization for the measurement of chlorine’s isotopic composition

Jedinjenja hlorata i perhlorata koja se koriste kao herbicidi, pogonska čvrsta goriva i eksplozivi, i sve češće se prepoznaju kao zagađivači podzemnih voda [1]. Perhlorati su posebno opasni jer ometaju proizvodnju hormona u štitnoj žlezdi. Hlor je podložan izotopskom frakcionisanju fizičkim i hemijskim procesima. Varijacije u atomskim masama, kao i u zastupljenosti izotopa hlora su posledica njegovog izotopskog frakcionisanja tokom fizičkih, hemijskih i bioloških procesa. Upravo, te varijacije su korisne za određivanje porekla supstance i proučavanje ekoloških, hidroloških i geoloških procesa. Takođe, analizom izotopa hlora može se utvrditi i priroda zagađivača životne sredine odnosno da li je njegovo poreklo antropogeno ili ne. Informacije mogu biti važne iz pravnih razloga i za remedijaciju kontaminiranog područja [2, 3]. Hlor se u prirodi javlja u obliku dva stabilna izotopa 35Cl i 37Cl (relativnih atomskih masa, respektivno 34,968 8527 i 36,965 9026), čiji relativni izotopski sastav je 0,7553 i 0,2547 [4]. Merenje odnosa stabilnih izotopa hlora (n(37Cl)/n(35Cl)), kao i molske frakcije 36Cl (n(36Cl)/n(Cl)) pruža korisne informacije o poreklu hlorata i perhlorata u okruženju [2, 3]. Ranija merenja promene odnosa stabilnih izotopa hlora rađena su pomoću magnetnog masenog spektrometra sa površinskom jonizacijom u negativnom modu direktnim praćenjem jona Cl- [5], ili određivanjem promena izotopskog sastava praćenjem jona jedinjenja CH3 Cl+ [6]. Danas se metodom površinske jonizacije radi ispitivanja izotopskog sastava ne prate direktno joni hlora, već jedinjenja kao što su „superalkalni” klasteri tipa M2 Cl+ (M-alkalni metali). Razlog je, vrlo niska energija jonizacije pomenutih klastera (u nekim slučajevima niža od energije jonizacije cezijuma) što omogućava njihovu vrlo jednostavnu detekciju u masenom spektru [7]. Iako je ova metoda precizna i pouzdana, vrlo je skupa. Broj analiza izotopa hlora pomoću ugljovodonika koji u sastavu imaju hlor kao što je trihloretilen je u porastu, jer su ove vrste važni zagađivači životne sredine. Analiza kontinuiranog protoka trihloretilena molekula, bilo gasnom hromatografijom/izotopskom masenom spektrometrijom (GC/IRMS) ili sa masenom spektrometrijom GC/kvadrupol (GC/qMS), je inovativno analitičko rešenje, ali uprkos ranijim implementacijama, nedostaje joj rutinska aplikacija [8]. Pored navedenih tehnika u površinske metode jonizacije spada i masenospektrometrijska metoda laserske desorpcije i jonizacije (LDI). Preliminarni rezultati ukazuju da se „superalkalni“ klasteri tipa M2 Cl+ mogu detektovati navedenom metodom. S obzirom na jednostavnost korišćenja i njenu ekonomsku isplatljivost, analiza i ispitivanje promene izotopskog sastava pomoću LDI metode može predstavljati važan korak u analitic

A run time adaptive architecture to trade-off performance for fault tolerance applied to a DVB on-board processor

Reliability is one of the key issues in space applications. Although highly flexible and generally less expensive than predominantly used ASICs, SRAM-based FPGAs are very susceptible to radiation effects. Hence, various fault tolerant techniques have to be applied in order to handle faults and protect the design. This paper presents a reconfigurable on-board processor capable of run-time adaptation to harsh environmental conditions and different functional demands. Run-time reconfigurability is achieved applying two different reconfiguration methodologies. We propose a novel self-reconfigurable architecture able to on demand duplicate or triplicate part of the design in order to form DMR and TMR structures. Moreover, we introduce two different approaches for voting the correct output. The first one is a traditional voter that adapts to different DMR/TMR domain positions whereas the second implies comparing the captured flip-flop values directly from the configuration memory read through ICAP. The comparison is done periodically by an embedded processor thus completely excluding the voting mechanism in hardware. The proposed run-time reconfiguration methodology provides savings in terms of device utilization, reconfiguration time, power consumption and significant reductions in the amount of rad-hard memory used by partial configurations

Structures and growth pathways of AunCln+3-(n≤7) cluster anions

Gold chloride clusters play an important role in catalysis and materials chemistry. Due to the diversity of their species and isomers, there is still a dearth of structural studies at the molecular level. In this work, anions of AunCln+3- and AunCln+5- (n = 2–4) clusters were obtained by laser desorption/ionization mass spectrometry (LDI MS), and the most stable isomers of AunCln+3- were determined after a thorough search and optimization at the TPSSh/aug-cc-pVTZ/ECP60MDF level. The results indicate that all isomers with the lowest energy have a planar zigzag skeleton. In each species, there is one Au(III) atom at the edge connected with four Cl atoms, which sets it from the other Au(I) atoms. Four growth pathways for AunCln+3- (n = 2–7) clusters are proposed (labelled R1, R2, R3 and R4). They are all associated with an aurophilic contact and are exothermic. The binding energies tend to stabilize at ~ −41 kcal/mol when the size of the cluster increases in all pathways. The pathway R1, which connects all the most stable isomers of the respective clusters, is characterized by cluster growth due to aurophilic interactions at the terminal atom of Au(I) in the zigzag chains. In the pathway of R4 involving Au-Au bonding in its initial structures (n ≤ 3), the distance between intermediate gold atoms grows with cluster size, ultimately resulting in the transfer of the intermediate Au-Au bonding into aurophilic interaction. The size effect on the structure and aurophilic interactions of these clusters will be better understood based on these discoveries, potentially providing new insights into the active but elusive chemical species involved in the corresponding catalytic reactions or nanoparticle synthesis processes

Endergonski autokatalitički ciklus fruktoze u efikasnoj proizvodnjI 5-Hidroksimetilfurfurala (5-HMF) iz spore pirolize mezokarpa goji bobica (GBM)

This paper considers possible uses of fruit-based waste (Goji berry mesocarp (GBM)) for the production of key platform chemicals (5-hydroxymethylfurfural (5-HMF)) through thermochemical conversion via slow pyrolysis, which was performed using simultaneous thermal analysis (STA). Originality and significance of this research is reflected in novel insights of fructose molecule role in the production of 5-hydroxymethylfurfural (5-HMF) through structural characteristics, manifesting reciprocal catalysis behaviour in an endergonic reaction pathway, giving high energy products. Based on proposed experimental and theoretical networks, the unwanted side products are totally blocked, where established results in this research clearly show advantages of synergistic work of the substrate molecule (glucose) and pseudo-catalyst (fructose) for the effective production of 5-HMF. The fructose self-repaired (isomerization) cycle through ‘open’ to ‘closed’ structure organization was explained as the key factor, which was responsible for the fructose effective autocatalytic lineage to the desired product, interpreting high yields of 5-HMF.Овај рад разматра могућу употребу отпада на бази воћа (Гоји бобица месокарпа (ГБМ)) за производњу кључних платформских хемикалија (5-хидроксиметилфурфурала (5-ХМФ)) кроз термо хемијску конверзију путем споре пиролизе, која је изведена коришћењем симултане термичке анализе (СТА). Оригиналност и значај овог истраживања огледа се у новим спознајама о улози молекула фруктозе у производњи 5-хидроксиметилфурфурала (5-ХМФ) кроз структурне карактеристике, манифестујући реципрочно понашање катализе у путу ендергонске реакције, дајући производе високе енергије. На основу предложених експерименталних и теоретских мрежа, нежељени споредни производи су потпуно блокирани, при чему утврђени резултати у овом истраживању јасно показују предност и синергистичког рада молекула супстрата (глукозе) и псеудо катализатора (фруктозе) за ефикасну производњу 5-ХМФ. Циклус фруктозе који се само поправља (изомеризација) кроз организацију „отворене“ до „затворене“ структуре објашњен је као кључни фактор, који је био одговоран за ефикасну аутокаталитичку линију фруктозе до жељеног производа, тумачећи високе приносе 5-ХМФ-а.The 10th ICREPS was held on October 17 and 18, 2022, in Chamber of Commerce and Industry, of Serbia, Belgrade

Analysis of design alternatives on using dynamic and partial reconfiguration in a space application

Some of the biggest concerns in space systems are power consumption and reliability due to the limited power generated by the system's energy harvesters and the fact that once deployed, it is almost impossible to perform maintenance or repairs. Another consideration is that during deployment, the high exposure to electromagnetic radiation can cause single event damage effects including SEUs, SEFIs, SETs and others. In order to mitigate these problems inherent to the space environment, a system with dynamic and partial reconfiguration capabilities is proposed. This approach provide s the flexibility to reconfigure parts of the FPGA while still in operation, thus making the system more flexible, fault tolerant and less power-consuming. In this paper, several partial reconfiguration approaches are proposed and compared in terms of device occupation, power consumption, reconfiguration speed and size of memory footprints

The AQUAS ECSEL Project Aggregated Quality Assurance for Systems: Co-Engineering Inside and Across the Product Life Cycle

There is an ever-increasing complexity of the systems we engineer in modern society, which includes facing the convergence of the embedded world and the open world. This complexity creates increasing difficulty with providing assurance for factors including safety, security and performance. In such a context, the AQUAS project investigates the challenges arising from e.g., the inter-dependence of safety, security and performance of systems and aims at efficient solutions for the entire product life-cycle. The project builds on knowledge of partners gained in current or former EU projects and will demonstrate the newly developed methods and techniques for co-engineering across use cases spanning Aerospace, Medicine, Transport and Industrial Control.A special thanks to all the AQUAS consortium people that have worked on the AQUAS proposal on which this paper is based, especially to Charles Robinson (TRT), the proposal coordinator. The AQUAS project is funded from the ECSEL Joint Undertaking under grant agreement n 737475, and from National funding

Reconstruction of fiber reinforcement in epoxy-based composite

Polymer matrix composites (PMCs) are very attractive materials due to a possibility to achieve versatile properties by combining with ceramic or metal reinforcement in different shapes and sizes. As a result, PMCs have found application in nearly every field, from household appliances to aerospace industry. Modern microelectronic devices contain conductive polymers with fillers that enhance their electrical properties. In addition, PMCs are being used as insulators and adhesives, contributing to the long life of electronic devices. Epoxy resins are the most commonly used insulators and adhesives. In order to improve their fracture toughness, glass fibers can be used as an efficient reinforcement. However, with the purpose of designing a composite with good mechanical properties and durability, deep knowledge of microstructure is required. In addition, microstructural analysis can be used to connect shape and size of pores or reinforcement with various physical properties. Fractal nature analysis is a valuable mathematical tool that can be employed for different shapes and forms rendering. In this manner, successful design and prediction of composite’s properties could be obtained. In this research, field emission scanning electron microscopy (FESEM) images were used for fractal analysis of glass fibers, with the aim of reconstructing the shape

Surface modification of TiO2 nanoparticles moderates neurological impairments and upregulated oxidative stress indicator in eyes of adult Wistar rats

Titanium dioxide nanoparticles (TiO2 NPs) are widely used in many daily necessities, including medicine, food/ beverages, and cosmetics. Besides the numerous benefits of TiO2 NPs utilization, their use raises public concerns since humans are exposed to their toxicity. As different alterations could moderate the observed side effects of commercially available bare TiO2 NPs, we investigated whether TiO2/SA NPs (TiO2 NPs surface‑modified with salicylic acid (SA)) impact the bare TiO2 NPs-induced sensory-motor impairments and eye level of 4-hydroxynonenal (HNE) as the final product of lipid peroxidation and indicator of oxidative stress. Our results demonstrate that 14 days following single oral treatment both investigated TiO2 NPs in adult Wistar rats affected neurological functions and promoted oxidative stress to different extents. Namely, the SA modification alleviated TiO2 NPs-induced asymmetry in four limb movement, while the hind limb clasping reflex and spontaneous activity scores were similar between TiO2 groups. In the eye crude membrane fraction of TiO2/SA NPs-treated rats in comparison to animals treated with bare TiO2 NPs, the HNE level was downregulated. Although SA exhibits the ability to reduce some TiO2 NPs toxicity, due to still unknown mechanism of TiO2 and TiO2/SA NPs actions, further studies are required to verify herein presented findingsNEURONS 2022 : October 15-17, Krakow, Poland, 2022